RALEIGH — Crews started making repairs this morning on the Herbert C. Bonner Bridge, which carries N.C. 12 over Oregon Inlet in Dare County.

They will repair, clean and paint the steel girders that comprise the three spans of the high-rise portion of the bridge over the main channel. Crews will cut out deteriorating sections of the girders and replace them with new steel. Once the new steel is in place, they will paint it to protect it from the elements.

Crews will do the work by standing on decking placed under the bridge. Special tarps will catch any of the old paint that falls off the bridge during the improvement process to protect the environment.

The decking will reduce the vertical clearance for vessels traveling through the navigational channel from 65 feet to 61 feet. The N.C. Department of Transportation has coordinated this change with the U.S. Coast Guard, which is alerting mariners through published notices and safety broadcasts on the radio.

Astron General Contractors was originally scheduled to start work on the $741,000 project in September 2011, but the repairs were postponed until this week due to the aftermath of Hurricane Irene. Weather permitting, the work is scheduled to be complete by May 22.

While the project is under way, motorists will encounter a lane closure along a one-quarter mile section of the bridge over the main channel. During the first few days of the project, the lane closure will be in place during daylight hours only. Following that period, it will go into effect 24 hours a day, seven days a week. Portable traffic signals will guide drivers through the work zone. NCDOT encourages them to go slow, pay attention and allow additional time to reach their destinations.

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